Description: Part of proof of Lemma E
in [Crawley] p. 113. Value of at an atom
not under .
TODO: FIX COMMENT TODO: consolidate uses of lhpmat29592
here and elsewhere, and presence/absence of term.
Also, why can proof be shortened with cdleme27cl29928? What is difference
from cdlemefs27cl29975? (Contributed by NM, 29-Mar-2013.)
(New usage is discouraged.)